updating xml_from_result to check for list_fields instead of field_names
diff --git a/system/database/DB_utility.php b/system/database/DB_utility.php
index 4ba69ad..33c68fa 100644
--- a/system/database/DB_utility.php
+++ b/system/database/DB_utility.php
@@ -217,7 +217,7 @@
 	 */
 	function xml_from_result($query, $params = array())
 	{
-		if ( ! is_object($query) OR ! method_exists($query, 'field_names'))
+		if ( ! is_object($query) OR ! method_exists($query, 'list_fields'))
 		{
 			show_error('You must submit a valid result object');
 		}